Prior to the present invention, a practical, efficient method of integrally dyeing polypropylene and certain other polymers has eluded researchers in the art.
Generally, when we speak herein of dyeable polymers such as dyeable polypropylene, we mean to include polymers receptive to the chemical addition or substitution of modifying groups other than dyes, as will become apparent to those skilled in the art. The fast dyeing of fabrics has long been accomplished through reliance on polar functionalities which are present in the fibers; the dyes are typically designed to react with the polar groups. Polypropylene, however, whether in the form of synthetic fiber or other more substantial three-dimensional form, must be colored through methods such as physical mixing of colorant or through a relatively expensive and frequently ineffective method of treatment. Pure polypropylene has no reactive groups at all, and of course no polar groups. To our knowledge, attempts to incorporate a monomer having reactive groups such as polar groups into the backbone of polypropylene by copolymerization have been failures. Typically such a monomer will not survive contact with the commonly used Ziegler-Natta catalyst and particularly the highly-active supported types of the present generation.
By integral dyeing, we mean a dyeing technique which employs "dyesites" as that term is used, for example, in U.S. Pat. No. 3,533,731. In this patent to Schmidl and Jennings, the dyesites are nitrogen-containing and are introduced by way of the monomer N,N-diisopropyl-7-octenylamine. The patent also recites the use of vinyl pyridine to provide nitrogen reactive sites for dyes. Such copolymers of propylene have not found widespread use because the reactivity of the functional nitrogen group makes it too vulnerable to unwanted reactions during the polymerization phase, i.e. in the presence of polymerization catalysts.
More broadly, it may be stated that prior to the present invention a practical method of employing supported Ziegler-Natta catalysts for the copolymerization of monomers containing functional groups has not been developed.
Silicon-containing polymers have been produced by hydrosilation of the unsaturated groups in polybutadiene--see U.S. Pat. No. 4,230,815. Small amounts of various polymerizable hydrolyzable silanes are employed in U.S. Pat. No. 4,481,322 as part of a filler including various di-unsaturated monomers.
A number of polymerizable silicone esters and silane monomers are disclosed in U.S. Pat. No. 4,454,295, and copolymerized with various acrylates and cellulose esters to make a material for use in manufacturing contact lenses. See also U.S. Pat. Nos. 3,504,998 and 3,709,656 which also employ various silicon-containing monomers.
A silane compound represented by the formula RSiR'.sub.n Y3.sub.-n wherein R is a member selected from the group consisting of ethylenically unsaturated hydrocarbyl and hydrocarbyloxy groups, R' is an aliphatic saturated hydrocarbyl group, Y is a hydrolyzable organic group, and n is zero, 1, or 2 is employed as a comonomer with ethylene and made to cross-link through the use of water in the presence of a catalyst to promote condensation linkages, in U.S. Pat. No. 4,297,310. Certain cyclic compounds are polymerized in U.S. Pat. No. 3,920,714 to produce polymers with silyl side groups, and certain polyenes containing silyl groups are shown in U.S. Pat. No. 4,028,483. Certain alpha-unsaturated compounds containing silyl-protected oxygen have been shown in the prior art in a context where they are not used for polymerization. See "Reaction of trialkyl (aryl) silanes with unsaturated -oxides", I. E. Sharikova and V. M. Al'bitskaya, Izv. Vyssh. Ucheb. Zaved., Khim. Khim. Tekhnol., 9(4), 595-599 (1966), In Russian; contains reference to H.sub.2 C.dbd.CH--CH.sub.2 --CH.sub.2 --O--SiEt.sub.3. The reaction parameters cited (boiling point=76-7.degree. C. at 11 mm Hg, density=0.826 g/ml) agree with the present specification. The compound was prepared from reaction of the -oxide of 1,3-butadiene and triethylsilane, in isopropanol in the presence of chloroplatinic acid (H.sub.2 PtCl.sub.6). No use of material was cited in the abstract. See "Reaction of triethylsilane with unsaturated alcohols" E Lukevics and M. G. Voronkov, Khim. Geterotsikl. Soedin., Akad. Nauk Latv. SSR, 1965(2), 179-86, In Russian. Primary alcohols (like allyl alcohol) react with triethylsilane in the presence of H.sub. 2 PtCl.sub.6 to form triethylsilyl enol ethers (like H.sub.2 C.dbd.CH--CH.sub.2 --O--SiEt.sub.3) with evolution of hydrogen. Secondary ethylenic alcohols (e.g. 1-buten-3-ol=H.sub.2 C.dbd.CHCH(OH)CH.sub.3) react to give the silyl ether (H.sub.2 C.dbd.CHCH(OSiEt.sub.3)CH.sub.3) and products of addition across the double bond [hydrosilation] (Et.sub.3 Si--CH.sub.2 --CH.sub.2 --CH--CH.sub.3) and (H.sub.3 CCH(SiEt.sub.3)CH.sub.2 CH.sub.3). No uses cited in the abstract. See "Allyloxy carbanions. New synthesis of aldehydes via a .beta.-acyl carbanion equivalent", W. Clark Still and T. L. Macdonald, J. Am. Chem. Soc. 1974, 96(17), 5561-3. H.sub.2 C.dbd.CH CH.sub.2 OSiEt.sub.3 is used to synthesize .beta.-alkylated aldehydes. See "Allyloxycarbanions. A synthesis of 3,4-dihydroxy-1-olefins from carbonyl compounds", W. Clark Still and T. L. Macdonald, J. Org. Chem. 1976, 41(22), 3620-2. H.sub.2 C.dbd.CHCH.sub.2 OSiR.sub.3 (R=Me, Et) gave stable allyl lithium reagents. See "Conversion of monoalkyl olefins to 1,1-dialkyl olefins by reaction with bis(cyclopentadienyl)titanium dichloride-trialkylaluminum", James J. Barber, Carl Willis, and George M. Whitesides, J. Org. Chem., 979, 44(20), 3603-4. Synthesis of (5-hexenyloxy) trimethyl silane which is H.sub.2 C.dbd.CH--(CH.sub.2).sub.4 --OSiMe.sub.3.
The reader may be interested in the following patents which disclose various methods of making dyeable polypropylene, none of which is similar to ours: U.S. Pat. Nos. 3,419,638, 3,779,703, and 3,131,990.
Special interest may be directed to U.S. Pat. Nos. 3,655,633, 3,857,825, 3,929,850, and 3,920,715 which disclose polymers having silyl end groups. In addition, it should be observed that the compounds 0-trimethylsilylallyl alcohol (CH.sub.3).sub.3 Si--OCH.sub.2 CH.dbd.CH.sub.2 and N-trimethyl-silylallylamine are known compounds offered for experimentation by Huls America (formerly Petrarch Systems) of Bristol, Pennsylvania. The compound 2-[(trimethylsilyl)oxy]ethyl methacrylate has been polymerized by Hirao, Kato, Yamaguchi and Nakahama as reported in Macromolecules 1986, 19, 1294-1299. The polymerization of certain monomers protected with silyl groups, specifically 4-vinyl phenol, 2-(4 vinylphenyl) ethanol, and 4-vinylaniline, are reported in the same article; however, none of the polymerizations is with a Ziegler-Natta catalyst. A series of hydrogenalkenyloxysilanes is reported in U.S. Pat. No. 4,294,975.
In addition to the above-recited prior art, we have become aware, through citation by the examiner in the parent application Ser. No. 947,960 of Garner U.S. Pat. No. 2,396,692, which shows the polymerization of ROSiR'.sub.3, for example where R contains an olefin group and R' may be an alkyl group; however, the polymerization is not effected by a Ziegler catalyst and is not stereospecific. Also cited was Natta et al U.S. Pat. No. 3,223,686, which copolymerizes certain silicon-containing monomers with ethylene; however, the silicon-containing monomers contain no oxygen. Bolchert, in U.S. Pat. No. 3,418,293, employs a Ziegler-type composition which in fact operates as an initiator to make polyvinyl alcohol using monomers of the formula CH.sub.2 .dbd.CHOSi(R).sub.3, achieving stereoregularity promoted by the non-polar nature of the solvent. Anderson, in U.S. Pat. No. 3,083,219 was also cited for its recitation that 3-buteneoxytrimethylsilane will polymerize with a specific Ziegler catalyst and the polymer can be hydrolyzed to form adhesive and coating compositions. The examiner also cited Boor, Jr., ZIEGLER-NATTA CATALYSTS AND POLYMERIZATIONS, Academic Press, Inc., London (1979), pages 532-533, which describes certain criteria to improve the ability of a polar compound to polymerize in a Ziegler-Natta system. Boor in turn cites U. Giannini, G. Bruckner, E. Pellino, and A. Cassata, J. Polym. Sci., Part B5, 527 (1967); Part C22, 157 (1968), which describes the inherent difficulty in homopolymerization of monomers containing -OSiR.sub.3 groups employing unsupported Ziegler-Natta catalysts. However, none of the references has the combination of factors and elements of our invention as expressed herein.